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Bug#711592: marked as done (kernel 3.2 x86: WCHAN column for procps is NOT working)

Your message dated Fri, 17 Jun 2022 13:35:47 +0200
with message-id <4757969.31r3eYUQgx@bagend>
and subject line Re: Bug#711592: Current x86 linux kernel is misconfigured.
has caused the Debian Bug report #711592,
regarding kernel 3.2 x86: WCHAN column for procps is NOT working
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.

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-- 
711592: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=711592
Debian Bug Tracking System
Contact owner@bugs.debian.org with problems
--- Begin Message --- 
Package: linux-image-686-pae
Version: 3.2+46

On current Debian kernels the the WCHAN column for procps is NOT working.
Run this command:
# cat /proc/*/wchan
For current Debian kernels you get all zeros, you should get something like: 
devtmpfsdsys_pauserescuer_threadbdi_sync_superskjournald2rescuer_threadhub_threadrescuer_threadrescuer_threadrescuer_threadscsi_error_handlerscsi_error_handlerscsi_error_handlerscsi_error_handlerscsi_
etc etc.
This is all due to the configuration of the frame pointers, there are two confgurations that work, the current release format isn't one of them... 

Current setting -- not working:
CONFIG_SCHED_OMIT_FRAME_POINTER=y
CONFIG_ARCH_WANT_FRAME_POINTERS=y
# CONFIG_FRAME_POINTER is not set

Working setting without frame pointers (except sched.o):
# CONFIG_SCHED_OMIT_FRAME_POINTER is not set
CONFIG_ARCH_WANT_FRAME_POINTERS=y
# CONFIG_FRAME_POINTER is not set

Working setting with frame pointers (Ubuntu):
CONFIG_SCHED_OMIT_FRAME_POINTER=y
CONFIG_ARCH_WANT_FRAME_POINTERS=y
CONFIG_FRAME_POINTER=y
The the "with frame pointers" method (like Ubuntu) gives more detailed information than "without frame pointers", but for me both are reasonable.
The CONFIG_SCHED_OMIT_FRAME_POINTER option is rather confusing, it only changes the compile options if it's NOT set. If it's set the frame pointer option says what we get. If it's not set an extra "no-omit-frame-pointer" is added to the compile of kernel/sched.c; so if the kernel is compiled with frame pointers it has no effect.
Note: This only applies to x86 and amd64; the "not working" combination where ALL frame pointers are omitted works fine on some processors, especially if it's impossible to remove the frame pointers anyway. 

IIRC: ARM needs frame pointers, Spark always has frame pointers.

--
Rob.                          (Robert de Bath <robert$ @ debath.co.uk>)
                                             <http://www.debath.co.uk/>

--- End Message ---
--- Begin Message --- 
Version:  5.16.14-1

On Tuesday, 14 June 2022 00:14:39 CEST Ben Hutchings wrote:
> Given that, I think this can be closed with version 5.16.14-1

Doing so now. If the bug can still be reproduced with a kernel 
version >=  5.16.14-1, feel free to reopen it.

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